Zombie fire ants wander in Texas — until heads fall off

It sounds like something out of science fiction: zombie fire ants. But it's all too real. Fire ants wander aimlessly away from the mound. Eventually their heads fall off, and they die. The strange part is that researchers at the University of Texas at Austin and Texas A&M’s AgriLife Extension Service say making "zombies" out of fire ants is a good thing.

It sounds like something out of science fiction: zombie fire ants. But it's all too real.

Fire ants wander aimlessly away from the mound.

Eventually their heads fall off, and they die.

The strange part is that researchers at the University of Texas at Austin and Texas A&M’s AgriLife Extension Service say making "zombies" out of fire ants is a good thing.

"It's a tool – they're not going to completely wipe out the fire ant, but it's a way to control their population," said Scott Ludwig, an integrated pest management specialist with the AgriLife Extension Service in Overton, in East Texas.

The tool is the tiny phorid fly, native to a region of South America where the fire ants in Texas originated. Researchers have learned that there are as many as 23 phorid species along with pathogens that attack fire ants to keep their population and movements under control.

So far, four phorid species have been introduced in Texas.

The flies "dive-bomb" the fire ants and lay eggs. The maggot that hatches inside the ant eats away at the brain, and the ant starts exhibiting what some might say is zombie-like behavior.

"At some point, the ant gets up and starts wandering," said Rob Plowes, a research associate at UT.

The maggot eventually migrates into the ant's head, but Plowes said he "wouldn't use the word 'control' to describe what is happening. There is no brain left in the ant, and the ant just starts wandering aimlessly. This wandering stage goes on for about two weeks."

About a month after the egg is laid, the ant's head falls off and the fly emerges ready to attack any foraging ants away from the mound and lay eggs.